The present invention relates to a POS system, and more particularly to a price look-up (PLU) file management system suitable to a scanning system.
A POS terminal installed at a point of sales issues a chit on which detail of merchandise which a customer purchased is printed. The detail printed on the chit includes not only merchandise codes but also names of merchandise and unit prices thereof for better understanding by the customer. Since the merchandise codes are inputed by a cashier through a keyboard or by a bar code, the POS terminal must have a file which manages the correspondence of the merchandise codes to merchandise names and unit prices thereof. This file is called a PLU file which is a table which allows retrieval of a merchandise name and a unit price by using the merchandise code as a key.
In a prior art POS system having the PLU file, the PLU files are provided in a register terminal and a host device as shown in JP-A-59-57368.
When merchandise which is not listed in the PLU file of the register terminal is to be transacted, an on-line query to the host device is made and the transaction is done at the register terminal based on the result of the retrieval of the PLU file of the host device.
However, this is very troublesome. In another proposal, a PLU file for all merchandise is provided in one of the POS terminals and the PLU file is divided into two hierarchy files, a local PLU which stores frequently referenced merchandise information and a center PLU which stores other merchandise information. In this system, file reconfiguration between the local PLU and the center PLU is controlled manually or other device such as a host computer. This is inconvenient in operation in retail stores in which well-selling merchandise vary day by day.